1. Field of Invention
This invention relates generally to musical instruments, specifically to stringed instruments, and more specifically to stringed instruments that can be converted easily from one type, of stringing such as a guitar, to another type, of stringing such as a banjo.
2. Prior Art
Guitars come in two types: acoustic, where no electrical pickups are provided on the guitar, and electrical, where electronic pickups are provided on the guitar for sending a signal representing the guitar's sound to an amplifier. Acoustic guitars produce a round sound and are used mainly for classical, flamenco, and folk music, while electrical guitars have a thinner sound and are used for mainly for jazz, country and western, and rock music, although the two types of guitars are often used interchangeably for the same type of music. Acoustic guitars come in two types: those with nylon strings (mellower sound) and those with steel strings (more metallic sound, scratch guard on body's face under strings, and thinner neck). They usually have a hollow wooden body with a thin front face or soundboard with a sound hole and a thin rear face, while electric guitars usually have a solid body. The bodies of both types usually have a figure-eight shaped outline, with electric guitars having one or two large notches or indentations in the smaller end for enabling the player to reach frets on the body. Both types have a neck extending from the smaller end of the body, with strings extending from the body to the distal end of the neck.
Banjos, on the other hand, usually have a circular body with a circular wooden or rigid frame and a skin or drumhead extending over the frame in lieu of a soundboard. A long neck with attached strings extends from the body. Banjos produce a twang-like, hollow, reedy sound and are used mainly for bluegrass and rural music, although, as with the two types of guitars, there is often considerable overlap between banjos and guitars for the same type of music.
A guitar usually has six strings. Assuming the guitar is held for play, with the neck on the player's left, these strings are numbered from 1 to 6, starting from the physically lowermost string. They are tuned as follows: 1-E; 2-B; 3-G; 4-D; 5-A; 6-E, with string 1 being thinnest and having the highest pitch (high E) and the strings progressing down in pitch to string 6, which has the lowest pitch (low E) and is thickest.
A banjo usually has five strings with the following tuning from highest pitch to lowest: 1-D; 2-B; 3-G; 4-D; 5-G.
Musicians often have to switch between banjos and guitars for different types of music. This requires that they carry and set up both types for a concert or performance. This is awkward, difficult, and expensive since it is necessary to buy, carry, and transport both instruments, keep both within easy reach in a safe spot during the performance, and set down one and pick up the other when switching.
U.S. Pat. No. 480,816 to Haney (1892) shows an instrument that Haney claims can be converted between a guitar and a banjo. To convert, two strings are removed and one is repositioned. This operation is awkward and impractical to perform.
Similarly, U.S. Pat. No. 1,634,730 to Travaglini (1927) shows an instrument with two necks and two respective bodies which are joined, one a guitar body and neck and one a banjo body and neck. This device is also awkward and would be expensive to produce.
U.S. Pat. No. 3,633,452 to Beasley (1972) also shows a combined guitar and banjo. A banjo head is provided in the guitar body and a mechanism is provided to selectively engage the strings with the banjo bridge. This arrangement is also awkward and expensive.
Various other stringed guitar and banjo-line instruments of interest have been patented. These do not solve the two-instrument problem above, but are mentioned as they are somewhat physically related to the present invention.
U.S. Pat. No. 607,359 to Forrest (1898) shows a five-string instrument with a device (FIG. 3) to produce tremolo. The fifth string is shorter and the portion of the neck beyond the tightening screw (b') for the fifth string is narrowed.
U.S. Pat. No. 3,392,618 to Pelensky (1968) shows a twelve-string guitar with a neck with two narrowing steps, similar to Forrest's.
U.S. Pat. No. 3,486,408 to Gross (1969) shows a guitar that can be converted to one with fewer strings by using a member to move selected strings away from the plane of play.
U.S. Pat. No. 3,834,267 to Shubb (1974) shows a slideable capo for the fifth string of a banjo.
U.S. Pat. No. 4,213,368 to Cox (1980) shows a banjo with a reinforced hole in the drumhead. Although not discussed, this banjo has a shorter fifth string and the portion of the neck beyond the tightening screw for the fifth string is narrowed, as with Forrest.
U.S. Pat. No. 4,738,178 to Deering (1988) shows an electric banjo with damped pickups. Although again not discussed, this banjo has a shorter fifth string and the portion of the neck beyond the tightening screw for the fifth string is again narrowed.